Lower Limb Flashcards
Calcaneus: Description
The calcaneus is the largest of the tarsal bones and is colloquially refered to as the heel bone.
Function: Inversion and eversion, transfer of force between the leg and the heel pad.
Location: below the talus
Calcaneus: Gross Anatomy
- Irregular box shaped bone
Features:
- Calcaneal tuberosity (heel) – posterior projection with:
- Lateral process
- Medial process
- Posteriorly – superior, middle (attachment for the Achilles) and inferior facet
- Sustentaculum tali – antero-medial process inferior to which is a groove from the flexor halluces longus
- Dorsal surface – location of the anterior, middle and posterior talocalcaneal facets, the tarsal sinus runs between the middle and posterior facets.
- Anterior process - anterior projection the anterior surface of which has the facet for the cuboid
Calcaneus: Articulation
- Talus via the anterior, middle and posterior articular facets
- Cuboid via the facet for the cuboid on the anterior surface
- Shares a joint space with the talonavicular joint forming the talocalcaneonavicular joint
Calcaneus: Relations
- Superior: talocalcaneal joint, talus, sinus tarsi
- Inferior: fad pad, long and short plantar ligaments
- Anterior: calcaneocuboidal joint, cuboid bone
- Posterior: Achilles tendon
- Medial: Tendon of flexor hallucis longus, deltoid ligament of the ankle, tibial nerve, posterior tibial artery
- Lateral: Tendons of peroneus longus and brevis
Calcaneus: Neurovasculature
- Medial and lateral calcaneal arteries from the posterior tibial and fibular arteries
- Artery of the tarsal sinus
Innervation:
- Tibial, sural and deep fibular nerves
Calcaneus: Variants
- Talocalcaneal coalition
- Calcaneonavicular coalition
- Os calcaneus secundaris
Femur: Description
Long bone of the thigh
Function: transfer force between the hip and leg
Femur: Gross Anatomy
Proximal portion:
- Head globular hemisphere covered in synovial cartilage except for the central fovea (attachment of ligamentum terres)
- Neck thinner process through which a large majority of the blood supply to the head flows
- Greater trochanter – large irregular lateral attachment site
- Lesser trochanter – conical posteromedial attachment site
- Intertrocanteric line anteriorly
- Intertrocanteric crest posteriorly
Shaft:
- Long
- Linea aspera – posterior ridge that serves as the attachment for multiple muscle and the intermuscular septa, 3 ridges superiorly becomes two ridges inferiorly that diverge to for the triangular popliteal surface
Distal:
- Flared head with two rounded synovial line condyles
- Synovial surface anteriorly for articulation with the patella
- Bilateral epicondyles superior to each condyle
Femur: Joints
Femoroacetabular – femoral head with the acetabulum, synovial ball and socket with fibrous capsule
Patellofemoral – between the patella groove and the articular surface of the patella
Tibiofemoral – between the medial and lateral condyles and the medial and lateral tibial plateau
Femur: Neurovasculature
Arterial:
- Artery of ligamentum terres
- Anterior and posterior humeral circumflex
- Perforating braches from profunda femoris
- Popliteal and genicular arteries distally
Venous:
- Anterior and posterior femoral circumflex veins to the greater saphenous veins
- Popliteal and deep femoral veins to the common iliac veins
Innervation:
- Femoral and tibial nerves
Femur: Variants
- Coxa valgus/varus
- Hip dysplasia
- Os acetabula
Patella: Description
The patella is the largest sesamoid bone in the human body. It lies within the quadriceps tendon / patellar ligament and forms part of the knee joint.
Patella: Articulation
Articular surface is covered in hyaline cartilage. It articulates with the trochlear groove of the femur (anterior distal surface between the medial and lateral condyles).
Patella: Gross Anatomy
- The patella is triangular in shape with a superior base and inferior apex.
- The posterior surface is smooth, composed of articular cartilage, and is divided into medial and lateral facets, which are sub divided into superior, middle and inferior portions.
- The lateral facet is the largest (this counters the tendency for the quadriceps to pull the patella laterally).
- The anterior surface is rough, for attachment of tendons and ligaments.
Patella: Attachments
Ligaments:
- Patellar ligament – from the apex of the patella to the tibial tuberosity
- Medial and lateral patellar retinaculum
- Medial and lateral patellofemoral ligament (MPFL and LPFL).
Muscles:
- Quadriceps tendon superiorly (really the same thing as the patellar ligament).
Patella: Relations
- superior: common tendon of quadratus femoris, suprapatellar bursa
- inferior: patellar tendon, infrapatellar bursa, infrapatellar fat pad
- lateral: lateral patellar retinaculum
- medial: medial patellar retinaculum
- posterior: knee joint, femur
- anterior: prepatellar bursa
Patella: Neurovsculature
Blood supply:
- Anastomotic rings formed from the branches of the superior and inferior geniculate arteries
Innervation:
- branches of nerves to vastus medialis and vastus lateralis
Patella: Variants
- bipartite patella
- multipartite patella
- absent patella
- variation in shape (see: Wiberg classification)
- dorsal defect of the patella (may occasionally be symptomatic)
Knee Joint: Description
The knee joint is a modified hinge joint between the thigh and the leg
Movements: Flexion and extension
Knee Joint: Gross Anatomy
Type: Synovial joint with a capsule (largest synovial joint in the body)
Articulations:
- Femoral condyles with tibial plateaus
- Patella with the patella groove of the femur
Knee Joint: Ligaments
- Medial collateral ligament
- Lateral collateral ligament
- Anterior cruciate ligament
- Posterior cruciate ligament
- Meniscofemoral ligaments
- Anterolateral and posterolateral ligaments
Knee Joint: Menisci
- Medial – larger, c-shaped, attached to the MCL laterally
- Lateral – smaller, almost a complete circle
Knee Joint: Bursa
- Pre-patella bursa
- Supra-patella bursa
- Deep and superficial Infrapatella bursa
- Semimembranous bursa
Knee Joint: Fat pads
- Hoffa’s deep to the patella tendon
- Suprapatella fat pad
Knee Joint: Neurovasculature
Arterial supply:
- Superior and inferior, medial and lateral, Genicular branches of the popliteal artery
- Descending genicular from the femoral
- Descending branch of the lateral circumflex
- Circumflex fibular
Venous: into the popliteal and femoral veins
Innervation: Femoral and genicular branches from the tibial and fibular nerves
Knee Joint: Variants
- Patella – dorsal patella defect, bipartite, absent
- Baker’s cyst
- Discoid meniscus
- Flabella
Hamstrings: Description
The hamstrings are the muscles of the posterior compartment of the thigh and include the:
- lateral: biceps femoris
- medial: semimembranosus and semitendinosus
Function: flex knee and extend hip
Hamstrings: Gross anatomy
Apart from the short head of biceps femoris, the muscles share two common features:
- span both the hip and knee joints
- originate from the ischial tuberosity
The short head of the biceps femoris originates from the linear aspera
Hamstrings: Biceps femoris
2 heads (long and short)
Origin is the Ischial tuberosity (long) and linea aspera (short)
Insertion is the fibular head
Innervation: tibial nerve
Artery: Inferior gluteal and popliteal artery
Hamstrings: Semitendinosus
Origin Ischial Tubersotirty
Accompanies semimembranoiss however forms tendon 2/3 down thigh
Inserts on the medial superior tibial condyle, pes anserisus posterior to the gracillis
Innervation: tibial nerve
Artery: Inferior gluteal and popliteal artery
Hamstrings: Semimembranosus
Origin Ischial tuberositiy
Inserts on the medial tibial condyle and posterior joint capsule
Innervation: tibial nerve
Artery: Inferior gluteal and popliteal artery
Hamstrings: Pes Anserius
- Sartorius
- Gracilis
- Semitendinoisis
Gastrocnemius: Attachments
- origin: above the lateral and medial femoral condyle
- insertion: calcaneal (Achilles) tendon into mid-posterior calcaneus
Gastrocnemius: Neurovasculature
- arterial supply: sural arteries
- innervation: tibial nerve (sciatic nerve nerve roots S1 and S2)
Gastrocnemius: Description
antagonist: tibialis anterior
action: plantar flexes foot and flexes knee
Gastrocnemius: Relations
- superficial to soleus
- forms the inferior borders of the popliteal fossa
Gastrocnemius: Variants
Fabella
Soleus: Attachments
- origin: fibula and medial border of the tibia (soleal line) via the inverted tendinous arch
- insertion: tendo calcaneus (Achilles tendon) into mid-posterior calcaneus
Soleus: Neurovasculature
- arterial supply: sural arteries
- innervation: tibial nerve (sciatic nerve roots L5 to S2)
Soleus: Relations
deep to the gastrocnemius
the popliteal artery and tibial nerve exit the popliteal fossa by passing under the tendinous arch
Soleus: Variants
- Accessory soleus Muscle
Arterial Supply of the foot: Description
Arterial supply of the foot is the vascular system that supplies oxygenated blood to the foot
Gross anatomy:
The arterial supply of the foot can be divided into plantar and dorsal components:
Medial Plantar artery
Origin: posterior tibial branch
Supplies: the medial side of the foot and the first toe
Termination: the 1 st medial plantar digital artery
Lateral Plantar artery
Origin: Posterior tibial artery
Course: Cross the foot toward the base of the 5 th metatarsal
Supplies: lateral intrinsic muscle of the foot
Termination: As the Plantar arch
Plantar arch
Connects the dorsalis pedis with the lateral plantar artery
Lies deep to the plantar aponeurosis
Branches: Plantar metatarsal arteries
Termination: connects with dorsalis pedis in the first metatarsal interspace
Dorsal Arterial Supply of the foot
Dorsalis pedis
Origin: Continuation of the anterior tibial artery
Course: Runs lateral to the extensor halluces longus tendon
Termination: continues as the first metatarsal artery
Branches:
- First dorsal metatarsal artery
- Medial tarsal arteries
- Lateral tarsal arteries
- Arcuate artery
- Dorsal metatarsal arteries
Popliteal Artery: Description
Large artery of the popliteal fossa
Supplies: Primary supply for the leg below the knee
Popliteal Artery: Gross Anatomy
Origin: A continuation of the superficial femoral artery as it passes out of the adductor hiatus
Course:
- Through the popliteal fossa where it is the deepest structure
- Through the fibrous arch of soleus
Termination:
Bifurcation into the anterior tibial and the tibioperoneal trunk
Popliteal Artery: Branches
Medial and lateral, superior and inferior genicular arteries
Middle genicular artery
Popliteal Artery: Relation
Popliteal artery is the most deep structure in the popliteal fossa
Deep to the popliteal vein
Popliteal Artery: Variation
- Trifurcation
- Peroneal from the anterior tibial
- High origin of the anterior tibial
- High origin of the posterior tibial
- Very long tibioperoneal trunk
- Hypoplastic infrapopliteal vessels
- Popliteal artery entrapment
Great Saphenous Vein: Description
The long and short saphenous veins are superficial veins of the lower limb
Function: return oxygenated blood from the lower limb to the iliac veins
Gross anatomy:
Both have valves
Origin: continuation of the medial marginal vein of the foot
Termination: Pierces the deep facia of the femoral triangle draining into the saphenofemoral junction. 99% have a valve within 2mm of the SFJ
Great Saphenous Vein: Course
It passes anterior to the medial malleolus, ascending in the saphenous space between the saphenous fascia superficially and the deep fascia, it is closely related to the saphenous nerve(s) below the knee.
Great Saphenous Vein: Tributaries
- Small saphenous vein
- Unnamed superficial veins of the leg
- Medial marginal vein of the foot
- Superficial epigastric
- Superficial circumflex iliac
- Superficial external iliac
- Superficial external pudendal
- Multiple deep perforators to the deep system
Lesser Saphenous Vein: Description
Origin: Confluence of the lateral aspect of the venous network of the dorsum of the foot
Termination: Pierces the deep fascia of the popliteal fossa to drain into the popliteal vein
Lesser Saphenous Vein: Course
Posterior to the lateral malleolus, ascending in the subcutaneous tissues of the lateral leg
Lesser Saphenous Vein: Tributaries
- Multiple unnamed superficial branches
- Great saphenous vein
- Multiple perforators to the deep venous system
Lesser Saphenous Vein: Relations
Course closely associated with the sural nerve
Lesser Saphenous Vein: Variants
- Vein of Giacomini
- Duplication
- Absence
- Fenestration
Talus: Description
The talus is a tarsal bone in the hindfoot that articulates with the tibia, fibula, calcaneus, and navicular bones. It has no muscular attachments and around 60% of its surface is covered by articular cartilage.
Talus: Gross anatomy
Body:
- The talar body has a curved smooth talar dome, which is covered with cartilage.
- Other parts of the talar body include the central portion, the posterior process and the lateral process.
Head:
- The talar head is the part that articulates with the navicular bone.
Neck:
- The talar head and body are connected by the talar neck, which is inclined downwards distally and medially.
- The medial surface of the talar neck has a sulcus, the sulcus tali, that forms the tarsal sinus with calcaneual sulcus of the calcaneum
Talus: Articulation
- Talar body: tibia, fibula and calcaneus
- Talar head: navicular bone
Talar ligaments
Lateral:
- Anterior talofibular ligament
- Posterior talofibular ligament
- Talocalcaneal ligaments
Deep:
Tarsal sinus ligaments:
- cervical ligament
- talocalcaneal interosseous ligament
Medial:
Deltoid ligament:
- anterior tibiotalar ligament
- posterior superficial tibiotalar ligament
- posterior deep tibiotalar ligament
Talus: Neurovasculature
Anterior and posterior tibial arteries
Peroneal artery
The vascular supply to the talus is considered tenuous due to the lack of muscular attachment to the bone
Innervation: deep peroneal nerve, tibial nerve, saphenous nerve, sural nerves
Talus: Variant anatomy
- talocalcaneal coalition
- the posterior process of the talus may not be fused to the central portion of the body, resulting in an os trigonum
- congenital vertical talus
Tibia: Description
The tibia is the largest bone of the leg and contributes to the knee and ankle joints. It is medial to and much stronger than the fibula, exceeded in length only by the femur.
Osteology
The tibia has a prismoid shaft, expanded ends, proximal larger condylar shelf articulating at the knee, and distal smaller end with a strong medial malleolus forming the ankle.
Tibia: Gross anatomy
Proximal tibia
- The tibia has a broad weight-bearing surface consisting of the medial and lateral condyles.
- The intercondylar area separates the medial and lateral plateau and is divided into the anterior and posterior areas.
- The tibial tuberosity is an anterior bony projection that receives the patellar tendon attachment and is separated from the skin by the subcutaneous infrapatellar bursa.
- Gerdy’s tubercle is located at the anterolateral aspect of the proximal tibia, where the iliotibial band (ITB) attaches.
Shaft
- The diaphysis of the tibia is triangular in cross section and has medial, lateral and posterior surfaces
Distal tibia
- The slightly expanded end of the tibia is rotated laterally (tibial torsion) and has five surfaces, namely, anterior, posterior, medial, lateral and distal. The lateral surface exhibits a triangular notch which attaches to the fibula.
TIbia: Articulations
The medial and lateral condyles articulate with corresponding femoral condyles at the knee. The lateral condyle of the proximal tibia has a circular facet articulating with the fibula at the proximal tibiofibular joint.
The distal articular surface of tibia is concave sagittal and slightly convex transversely. The concave surface (also called the sellar surface) fits over the dome of talus at the talocrural joint (a.k.a. tibiotalar joint)
Tibia: Musculotendinous attachments
- tensor fascia latae muscle at Gerdy’s tubercle via the iliotibial band
- quadriceps femoris at the tibial tuberosity
- sartorius, gracilis, semitendinosus form a wide insertional slip called the pes anserinus with an underlying pes anserine bursa
- horizontal head of semimembranosus inserts at medial condyle
- popliteus at posterior tibia above the soleal line.
Tibia: Muscular origins
- tibialis anterior muscle at the lateral tibia
- extensor digitorum longus along the lateral tibial shaft
- soleus muscle from the soleal line on the posterior tibia
- flexor digitorum longus muscle on the posterior tibia distal to soleal line.
Tibial Ligaments
- Medial and lateral collateral ligaments of the knee
- Anterior and posterior tibiotalar
- Tibiocalcaneal
Tibia: Neurovasculature
Blood supply:
- Geniculars
- Anterior and posterior tibial
Nerve supply
Proximally innervated by branches supplying the knee joint, distally by those supplying the ankle. The periosteum of the diaphysis receives nerve twigs from the overlying muscles attaching to the tibia.
Tibia Variant anatomy
Ball and socket ankle joint
Fibula: Description
The fibula is the smaller of the two bones of the leg. It is not directly involved in the transmission of weight but is important for ankle stability and acts as a source for numerous muscle attachments.
Osteology
Consists of a head, neck, shaft and distal malleolus.
Fibula: Gross anatomy
Head
- The proximal head is irregular with a small superiorly pointed tubercle called the styloid process.
- The proximomedial head articulates with the tibia to form the superior tibiofibular joint via a rounded facet.
- The neck is just inferior to the head.
Shaft
Triangular in shape
Lateral malleolus
The lateral malleolus forms the lateral part of the mortise and extends more distally and posteriorly than the medial malleolus.
Fibula: Articulations
The fibula contributes to the ankle joint but is not involved in the knee joint directly:
- Proximal: superior tibiofibular joint
- Distal: talocrural joint, inferior tibiofibular joint (tibiofibular syndesmosis joint)
Fibular attachments
Musculotendinous
Proximal/head
- biceps femoris
- extensor digitorum longus
- soleus
Medial surface
- extensor digitorum longus
- peroneus tertius
- extensor hallucis longus
Lateral surface
- peroneus longus
- peroneus brevis
Posterior surface
- tibialis posterior
- soleus
- flexor hallucis longus
Fibula: Ligaments
- Anterior and posterior proximal tibiofibular ligaments
- Fibular collateral ligament of the knee joint
- Interosseous membrane
- Anterior inferior and posterior inferior tibiofibular ligaments
- superior extensor retinaculum and superior peroneal retinaculum of the ankle
Fibula: Relations
The lateral part of the fibular neck accommodates the common fibular nerve. The peroneus longus and brevis tendons pass behind the lateral malleolus with the peroneus tertius passing in front.
In relation to the fascial compartments of the leg:
- the anterior compartment sits anterior to the fibula
- the lateral compartment sits lateral to the fibula
- the deep posterior compartment sits medial to the fibula
- the superficial posterior compartment sits posterior to the fibula
At the lateral malleolus, the peroneus brevis tendon passes behind the malleolus closest to the bone, anterior to the peroneus longus tendon (memory aid: brevis closest to bone).
Fibula: Neurovasculature
Arterial:
Perforators of Fibular artery branch of the tibioperoneal trunk
Venous:
Fibular vein draining into the TP trunk / popliteal veins
Innervation:
Common fibular nerve
Fibula: Variant anatomy
Fibular hemimelia
Os sub fibulare
Ball and socket talocrural joint
Hip Joint: Description
Deep synovial ball and socket joint between the femoral head and the acetabulum (roman vinegar cup!).
Movements:
Flexion, extension, abduction, adduction, internal and external rotation
Hip Joint: Gross anatomy
- Acetabulum formed by the fusion of the ishium, ilium and pubis, cup like, deepened by the fibrocartilage labrum.
- The labrum encircles the acetabulum and is completed inferiorly by the transverse acetabular ligament.
- Femoral head, globular lined with synovial cartilage except for central fovea.
- Capsule from the labrum to intertrocanteric crest and line.
Hip Joint: Ligaments
- Ischiofemoral
- Iliofemoral
- Pubofemoral
- Transverse acetabular
- Ligamentum teres
Hip joint: Neurovasculature
Blood supply:
- Medial and lateral circumflex femoral
- Artery of ligamentum teres
Nerve:
- Femoral and obturator nerves
Hip joint: Bursae
- Trochanteric
- Iliopsoas
- Gluteus Medius
Hip joint: Variants
- Developmental hip dysplasia
- Coxa valga and vara
- Labrum variation – triangular / round / absent
- Os acetabula – superior acetabulum
Talocalcaneal joint: Description
The talocalcaneous joints are distal to the ankle joint and is locates where the talus rests on the calcaneus allows inversion and eversion.
Talocalcaneal joint: Gross anatomy
Synovial joint with hyaline cartilage surrounded by capsule
Talus covered with 60% surface with hyaline cartilage
Planar joints of the talocalceaneal joints
Anterior, middle and posterior articulations with sinus tarsi running between the middle and posterior articulations
Talocalcaneal ligaments
- Spring ligament – sustentaculum tali to navicular
- Interosseous talocalcaneal lig. Thick ligament in sinus tarsi
- Anterior, posterior, medial and lateral talocalcaneal ligaments
Talocalcaneal joints: Neurovasculature
Arterial supply:
Anterior and posterior tibial arteries
Peroneal artery
The vascular supply to the talus is considered tenuous due to the lack of muscular attachment to the bone
Innervation: deep peroneal nerve, tibial nerve, saphenous nerve, sural nerves
Talocalcaneal joint: Variants
Talocalcalcanous coalition of middle facet, posterior or anterior
Absent talus
Ball and socket talocural joint
Patellofemoral joint: Description
The patellofemoral joint is a saddle joint which is lined with hyaline cartilage (synovial) and sits between the distal femur and articular facets of the patella
Patellofemoral joint: Gross anatomy
- Inverted pyramid shaped sesamoid bone of the patella sits within the quadriceps and patella tendon
- Medial and lateral articular facets on the posterior surface articulate with the medial and lateral patella groove of the femur
- The lateral facet is the steepest facet
- Fibrous capsule and synovial membrane continuous with the knee joint
Patellofemoral joint: Ligaments
- Patellar ligament – from the apex of the patella to the tibial tuberosity
- Medial and lateral patellar retinaculum
- Medial and lateral patellofemoral ligament
Patellofemoral joint: Relations
Anterior: patella, prepatella bursa
Posterior: Femur and femoral condyles with intercondylar groove
Inferior: Patella tendon, infrapatellar bursa and Hoffa’s fat pad
Superior: Quad tendon and suprapatellar bursa
Medial and lateral: patellar retinaculum
Patellofemoral joint: Neurovasculature
Arterial:
Medial and lateral, superior and inferior genicular arteries.
Descending branch of geniculate from femoral profunda
Innervation:
Femoral , tibial and common peroneal nerve
Patellofemoral joint: Variants
Bipartite patella
Dorsal patella defect
Absent patella
Lateral collateral ligaments of the ankle: Description
A set of three ligaments of the lateral aspect of the ankle
Function: Stabilise the ankle, resist inversion
Anterior talofibular ligament
- Horizontal course
- From the anterior marginal of the lateral malleolus to the lateral talus
Calcaneofibular joint
- Vertical course
- From the inferior aspect of the lateral malleolus to the lateral calcaneus
Posterior Talofibular ligament
- Horizontal course
- Distal lateral malleolar fossa to the lateral tubercle of the posterior talar process
- Inserts into an Os trigonum if present
Superficial medial collateral ligaments
- Tibionavicular
- Tibiocalcalcaneal
- Posterior superficial tibiotalar ligament
- Tibiospring ligament
Deep medial collateral ligaments of the ankle
Anterior tibiotalar
Posterior deep tibiotalar ligament
ACL: Description
Anterior cruciate ligament (ACL) is one of the two cruciate ligaments that stabilise the knee joint.
ACL: Gross anatomy
The ACL arises from the anteromedial aspect of the intercondylar area on the tibial plateau and passes upwards and backwards to attach to the medial aspect of the lateral femoral condyle. (ALP)
Like the posterior cruciate ligament, the ACL is intracapsular but extrasynovial.
The ACL consists of two components:
- anteromedial bundle (AMB)
- posterolateral bundle (PLB)
PCL: Description
The posterior cruciate ligament (PCL) is one of the two cruciate ligaments that stabilise the knee joint.
PCL: Gross anatomy
The PCL attaches to the posterior intercondylar area and passes anterosuperiorly to insert into the lateral surface of the medial femoral condyle.
When the knee is in extension, it makes an almost 90º turn as it passes anterosuperiorly. The anterior cruciate ligament passes lateral to it and curves around it.
The PCL is intracapsular but extrasynovial and is approximately 13 mm in diameter. It contains two fibre bundles named according to their relative attachments:
- anterolateral
- posteromedial
Menisci of the knee: Description
The knee menisci are fibrocartilaginous structure that sit within the knee joint, deepening the tibiofemoral articulation.
Function: Improve stability, shock absorption and load transmission
Menisci of the knee: Gross anatomy
- Two per knee joint medial and lateral.
- Central body with anterior and posterior horns,
- Triangular in cross section being thicker peripherally
Medial meniscus:
- C-shaped
- Larger of the two
Lateral meniscus:
- Almost complete circle
- Smaller of the two
Medial meniscus: attachments
- Anterior horn – intercondylar area anterior to the attachment of the anterior cruciate ligament, transverse meniscal ligament
- Body – attached to the medial collateral ligament
- Posterior horn – to the posterior intercondylar area between the PCL insertion and the posterior root attachment of the lateral meniscus
Lateral meniscus: Attachments
- Anterior horn – lateral to the ACL insertion, transverse meniscal ligament
- Body – closely related to the popliteus tendon
- Posterior horn – posterior intercondylar area posterior to the attachment of the posterior horn of the medial meniscus
- Anterior and posterior meniscofemoral ligaments – from the posterior horn to the lateral aspect of the medial femoral condyle
Menisci: Neurovaculature
Blood supply:
- Arterial: Genicular arteries
- Venous: Genicular veins
Innervation:
- Tibial and femoral nerves
Lymphatics:
- Inguinal nodes
Menisci: Variants
- Discoid meniscus
- Hypoplastic or absent
- Speckled anterior horn
- Meniscal ossicle
Gluteus maximus
- Thick flat sheet muscle of the buttock, most superficial sloping down
- Origin: Gluteal surface of the ilium bone, lumbar fascia, lateral sacrum
- Insert: Gluteal tuberosity of femur and iliotibial tract
- Nerve: Inferior gluteal nerve from L5-S2 sacral plexus
- Blood: Inferior gluteal artery from anterior division of the internal iliac artery
- Action: Extend hip and internal rotation
Gluteus medius
- Below the glut max and fan shaped
- Origin: Gluteal Surface of ilium bone between the anterior and posterior gluteal line
- Insert: Posterolateral portion of the greater trochanter of femur
- Nerve: Superior gluteal L4-S1 sacral plexus
- Blood: Superior and inferior gluteal artery
- Action: internal rotation and abduction
Gluteus minimus
- Deepest muscle of the buttocks, covered by glut. Med.
- Origin: Gluteal surface of ilium between the anterior and inferior gluteal line
- Insert: anterior surface of greater tuberosity
- Nerve: Superior gluteal L4-S1
- Blood: sup and inferior gluteal from IIA
- Action: internal rotation and abduction
Gluteus: Variants
- Gluteus Quartus is a accessory muscle between the medius and minimus
- Fusion of glut max and tensor fascia lata
- May be fused with piriformis
Gluteus: Relations
- Inferior gluteal nerve runs between the minimus and medius
- Sciatic nerve emerges deep to the glut max with the inferior gluteal nerve and art
Fibularis longus and brevis: Description
Both are muscle of the anterior compartment of the leg. Course together with a shared synovial sheath. Together the tendons wrap around the lateral malleolus, specifically within the retromalleolar groove of the distal fibula (brevis tendon is close to bone here).
Fibularis longus
- origin: head of the fibula
- insertion: first metatarsal and medial cuneiform
- action: plantar flexion and foot eversion
- arterial supply: fibular artery
- innervation: superficial fibular nerve
- antagonist: tibialis anterior
Fibularis brevis
- origin: lower two thirds of lateral surface of the fibula
- insertion: lateral tubercle at base of fifth metatarsal
- action: plantar flexion and eversion of foot
- arterial supply: fibular artery (peroneal artery)
- innervation: superficial fibular nerve
Sartorius: Description
The longest muscle in the body, crosses the hip and knee joint therefore acting on both joints. Latin for Tailor.
Sartorius: Gross anatomy
Origin: ASIS from the iliac crest
Course:
- Runs obliquely across thigh
- Forms the lateral wall of the femoral triangle
- Forms the roof of the adductor canal at lower femoral triangle
- Covers superficial femoral artery and saphenous nerve deep in this canal
- Medial femoral cutaneous runs medially along muscle
Insertion:
Medial super tibia as part of pes anserinus
Actions:
Flexion and external rotation of the thigh, cross leg movement
Sartorius: Neurovasculature
Innervation:
Femoral Nerve L2-4
Arterial:
Superficial femoral artery
Vein:
Greater saphenous and superficial femoral vein
Sartorius: variants
- The origin may be from the inguinal ligament or pubis
- Tendon may merge early with the semimembranosus tendon
Quadratus femoris: Description
The quadriceps is the group of 4 muscles in the anterior compartment of the thigh that connect to the patella via the quadriceps tendon. The muscles are:
Rectus Femoris
- origin: straight head originates from the anterior inferior iliac spine (AIIS) of the ilium, the reflected head originates from the ilium just superior to the acetabulum
- insertion: quadriceps tendon
Vastus medialis
- origin: shaft of femur linea aspera
- insertion quadriceps tendon and medial border of patella
Vastus lateralis
- origin: shaft of femur linea aspera
- insertion quadriceps tendon and lateral border of patella
Vastus intermedius
- origin: upper two thirds of the anterior and lateral surfaces of the femur
- insertion: quadriceps tendon, lateral margin of patella and lateral condyle of tibia
Quadriceps femoris: Neurovasculature
Innervation:
All four muscles are innervated by the femoral nerve.
Arterial:
All four muscle are supplied by the lateral femoral circumflex
Common peroneal N: Gross anatomy
Origin: distal thigh superior to the popliteal fossa
Course:
- Through the popliteal fossa laterally
- Winds around the fibula neck
- Enters the lateral compartment of the leg
Supply:
motor supply: short head biceps femoris
sensory supply: cutaneous innervation of posterolateral leg
Peroneal N: Branches
- deep peroneal nerve – nerve to the anterior compartment of the leg, runs on the interosseous membrane with the anterior tibial artery, supplies sensory to the first webspace
- superficial peroneal nerve – nerve supplying the lateral compartment of the leg, sensory to the dorsum of the foot
Peroneal N: Relations
- Deep peroneal – runs on the anterior surface of the interosseous membrane with the anterior tibial artery
- Superficial peroneal – in the lateral compartment of the leg with fibularis longus and brevis
- Common peroneal runs around the neck of the fibula
Peroneal N: Variants
- Aberrant path
- High division
- No sciatic nerve
Sciatic N: Description
The sciatic nerve arises from the sacral plexus from the roots of L4-S3. It is the longest and widest single nerve in the body.
Sciatic N: Gross anatomy
origin: sacral plexus (L4-S3)
course:
- exits the pelvis through the greater sciatic foramen
- courses inferiorly through the posterior compartment of the thigh
- Divides in the mid-thigh
Sciatic N Branches
- tibial nerve(L4-S3)
- common peroneal nerve(L4-S2)
The tibial nerve is the nerve to the posterior compartment of the leg
The common perioneal nerve supplies the anterior and lateral compartments of the leg
Sciatic N: Relations
- Anterior: Deep femoral artery and vein
- Posterior: Hamstrings
- Leaves the greater sciatic foramen inferior to piriformis
Sciatic N: Variants
- The division of the sciatic nerve into the tibial and common fibular can happen at any point
- Sciatic nerve above piriformis
- Sciatic nerve through piriformis
- Persistent sciatic artery (may be the dominant artery to the leg)
Femoral N: Description
The femoral nerve is the nerve to the anterior compartment of the thigh
Function: Motor to the anterior compartment, sensory to the anterior and medial thigh
Femoral N: Gross anatomy
Origin: Lumbar plexus, Roots L2, 3, 4
Course: It passes out from the lateral boarder of psoas
It passes through the retroinguinal space lateral to the common femoral artery
It lies outside the femoral sheath
Termination:
Divides in the superficial and deep divisions
Femoral N: Divisions
Superficial:
- Innervate sartorius and the sensory to the anterio-medial thigh
Deep division continues:
- Large anterior thigh muscle innervation
- Continues as saphenous nerve which runs through the adductor hiatus then with the great saphenous vein and supplies sensation to the medial leg
Femoral N: Variants
Multiple femoral nerve slips within psoas
Femoral Artery: Description
The femoral artery is the primary arterial supply trunk of the lower limb with branches to the anterior abdominal wall.
Common femoral artery: Gross description
Origin: Continuation of the external iliac artery after passing medial to the midpoint of the inguinal ligament
Course: Short course in the femoral triangle
Termination: Branches to become the profunda femoris and the superficial femoral artery
Common femoral artery: Branches
- Superficial epigastric
- Inferior epigastric
- Superficial circumflex iliac
- Superficial and deep external pudendal
Profunda femoris
Origin: Posterior aspect of the common femoral artery
Course: posteriodistally
Main branches:
Medial and lateral circumflex femoral arteries
(Desending lateral circumflex)
Termination: Within the thigh as perforating arteries
Superficial femoral artery
Origin: continuation of the common femoral artery after the profundal femoris branch
Course: down the leg deep to satorious enters the adductor canal
Termination: adductor hiatus becomes the popliteal artery
Branches: descending geniculate branch
Boundaries of the femoral triangle
SAIL
- Lateral - Sartorius
- Medial - Adductor longus
- Superior - Inguinal ligament
- Floor - iliopsoas (laterally) and pectineus (medially)
- Roof - Fascia lata
Femoral triangle: Contents
Femoral – nerve, artery, vein (lateral to medial)
Femoral sheath – thickening of the deep fascia of the thigh
Lymphatic drainage of the lower leg: Superficial inguinal
The superficial inguinal nodes are located in the superficial fascia of the upper thigh near the inguinal ligament and great saphenous vein. They number around 10 and drain lymph from the gluteal region, inferior anterior abdominal wall, perineum and superficial lower limbs. They drain into the external iliac lymph nodes via channels accompanying the femoral vessels.
Lymphatic drainge of the lower limb: Deep inguinal nodes
The deep inguinal nodes are located within the femoral sheath, medial to the femoral vein. They receive afferent lymphatic drainage from the deep lymphatics of the distal lower extremity and perineum (e.g. glans penis / clitoris), and drain proximally into external iliac lymph nodes via channels running with the femoral vein. The deep nodes also share common channels with the superficial inguinal nodes.
Lymphatic drainage of the lower limb: Popliteal nodes
The popliteal nodes are small collection of deep nodes posterior to the knee and they are close to the popliteal vessels. They drain lymph from superficial vessels, which accompany the small saphenous vein, as well as, deep areas of the leg and foot. They drain into the deep and superficial inguinal nodes.
Popliteal fossa: Description
The popliteal fossa is a diamond or rhomboid-shaped fat-filled space in the posterior knee.
Popliteal fossa: Boundaries
superolateral: medial border of biceps femoris
superomedial: lateral border of semimembranosus (with semitendinosus superficial to it)
inferolateral: medial border of the lateral head of gastrocnemius
inferomedial: lateral border of the medial head of gastrocnemius
floor: (superior to inferior) femur (popliteal surface), knee joint capsule, popliteus muscle
roof: skin, subcutaneous tissue, fascia lata
Popliteal fossa: Contents
AVN medial to lateral
fat
- popliteal artery: deepest, gives off genicular branches
- popliteal vein: in between the artery and tibial nerve
- tibial nerve: most superficial
- small saphenous vein: ascends and pierces the roof to enter the popliteal vein
- popliteal lymph nodes
Tibial plateau: Description
The tibial plateau is the proximal articular surface of the tibia.
TIbial plateau: Gross anatomy
The tibial plateau is composed of two parts:
Concave articular surfaces of the oval-shaped medial and circular-shaped lateral tibial condyles
Intercondylar eminence – site of the attachment of the menisci and cruciate ligaments
Tibial tuberosity – anterior attachment site for the patella ligament
Tibial plateau: Neurovasculature
Blood supply:
Genicular arteries and veins
Innervation:
Femoral, Tibial and peroneal nerves
Lymphatics:
Inguinal
Tarsal tunnel: Description
The tarsal tunnel is a fibro-osseous canal found in the medial aspect of the ankle.
Tarsal tunnel boundaries
- roof: flexor retinaculum
- floor: medial surfaces of the tibia, talus and calcaneus
Tarsal Tunnel: Contents
- From anterior to posterior:
- tibialis posterior tendon
- flexor digitorum longus tendon
- posterior tibial artery and vein
- tibial nerve: divides into the medial and lateral plantar nerves within the tunnel
- flexor hallucis longus tendon
Adductor Canal
Description:
- Aponeurotic tunnel in the middle third of the thigh
- Extending from the apex of the femoral triangle to the opening between the adductor magnus oblique and medial heads (the adductor hiatus)
Boundaries:
- Anteriorly: sartorius
- Postermedially: adductor longus, adductor magnus
- Laterally: vastus medialis
Contents:
- Femoral artery
- Femoral vein
- Branches of the femoral nerve (saphenous nerve, nerve to the vastus medialis)
- Neither of these branches enter the adductor hiatus
- The saphenous nerve does not go through adductor hiatus passes medially between sartorius and gracillis
- The nerve to vastus medialis supplies the muscle prior to the adductor hiatus
